1. Field of the Invention
The present invention relates to an image forming system including a plurality of image forming apparatuses coupled together, and relates to a control apparatus, a control method and a storage medium therefor.
2. Description of the Related Art
An image forming system (hereinafter, also referred to as the printing system) has been known that includes image forming apparatuses coupled together to perform printing on recording sheets (see, for example, Japanese Laid-open Patent Publication No. 2006-58881).
In such a printing system, an image forming apparatus disposed on the upstream side in a recording sheet conveyance direction (hereinafter, referred to as the upstream image forming apparatus) performs printing on one surfaces e.g., front surfaces, of recording sheets and an image forming apparatus disposed on the downstream side in the sheet conveyance direction (hereinafter, referred to as the downstream image forming apparatus) performs printing on the other surfaces, e.g., rear surfaces, of the recording sheets.
By means of the printing system including two image forming apparatuses coupled together, double-sided printing can be performed at a higher speed than when the double-sided printing is performed by a single image forming apparatus.
Meanwhile, some image forming apparatus can assume a waiting state where a fixing unit of the apparatus is held at a predetermined temperature so as to be ready for immediately starting printing. Such an waiting state is generally called a standby state.
Depending on the purpose of use of a printed product, printing is performed on only one surfaces or both surfaces of recording sheets that constitute the printed product. To perform one-sided printing by a printing system having two image forming apparatuses, it is enough to use one of the two image forming apparatuses.
Conventionally, among the two image forming apparatuses, the image forming apparatus not used for one-sided printing is held in a standby state where the fixing unit is adjusted at a predetermined temperature so as to be able to respond to a job command given by a user.
However, if the image forming apparatus not used for the one-sided printing is held in the standby state to wait for reception of the job command, electric power is unnecessarily consumed and the service life of component parts of the apparatus is adversely affected.